


The Colors of Tsuna

by VongolaDecima



Category: Katekyou Hitman Reborn!
Genre: Fluff, Humor, Other
Language: English
Status: Completed
Published: 2016-11-20
Updated: 2017-10-27
Packaged: 2018-09-01 00:28:30
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 8
Words: 4,039
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8599855
Author URL: https://archiveofourown.org/users/VongolaDecima/pseuds/VongolaDecima
Summary: All Tsuna had wanted to do was finish his accursed paperwork. But could he?No!Instead, he had to be the test subject for the new Rainbow Bullet. He truly regrets not making a run for it in the end.





	1. The Original

* * *

Tsuna sighed in exasperation at the sight of Reborn and Verde. All he wanted to do was finish his accursed paperwork until the two Arcobaleno, now adults, walked in. Now, all three of them were standing in one of the training rooms. Sky flame igniting upon his forehead, he looked at the Lightning Arcobaleno. “Do I really have to do this?” Verde rolled his eyes at the Vongola boss’s question. Pushing up his glasses, he looked at Tsuna and said, “If it will help, think of it as training.” The scientist only received a blank stare from Tsuna. Reborn simply smirked before raising his hand up to show a strange bullet.

 

It resembled the dying will bullet with the exception of it being gold with a multicolored flame on it. “It’s called the Rainbow Bullet, and you’re going to help us test it out.” Tsuna sighed quietly, his hyper intuition warning him something bad was going to go happen. Verde stood to the side with a clipboard in hand, ready to take notes. Leon crawled from his spot on Reborn’s fedora and to his master’s hand before morphing into a familiar green gun. Placing the bullet within the chamber, Reborn cocked it before pointing it toward Tsuna.

 

When Reborn pulled the trigger, Tsuna couldn't help but regret not running away.


	2. Cloud User

When the Rainbow Bullet pierced Tsuna’s forehead, it extinguished his Sky flame before he fell onto his back. Verde was jotting down notes quickly, watching to see what kind of reaction Tsuna would have with the bullet. For the next three seconds, the Vongola Boss didn’t make a single move before a Cloud flame appeared in the place of his Sky flame. Tsuna opened his eyes slowly, revealing the change in color. The brunet got up slowly, his eyes narrowing slightly at the sight of Reborn and Verde.

 

“A cloud flame? How interesting.” Muttering to himself, Verde scribbled down extra notes from the change in Tsuna’s flame. After writing something extra down, Verde looked at Tsuna and asked,  “How do you feel, Tsuna?” Tsuna’s narrowed gaze slowly slinked over to Verde before he answered with a simple reply. “Hn.” Silence soon filled the room from Tsuna’s reply. The two Arcobaleno were reminded of a certain Cloud guardian.

 

Snapping out of his surprised state, Verde quickly scribbled down information on his clipboard. If he was certain, Tsuna probably developed his Cloud guardian’s personality. Reborn smirked, unable to hide the fact he was amused by the turn of events. Both Verde and Reborn made eye contact, a silent message passing between the two. Soon enough, Reborn looked away and turned his gaze upon Tsuna. “We’re done for today.” Missing the mischievous glint shining in the Sun Arcobaleno’s eye, Tsuna nodded and made his way out of the training room.

 

* * *

 

Yawning quietly, Tsuna made his way down a hall within the mansion. Turning around the corner, he bumped into someone. “Kufufu, if it isn’t Tsunayoshi.” Recognizing the voice, the brunet’s eyes narrowed in slight annoyance. Lifting his head up, he made eye contact with the male counterpart of the mist. Blinking slightly in surprise, Mukuro smirked at the sight in front of him. “What an interesting sight.” He took notice of the change of color in Tsuna’s eyes and sky flame. “Hn, pineapple.” For some reason, the air became tense around the two. Mukuro’s eyebrow twitched, his smile looking strained as he said, “What was that?” A smirk slowly graced Tsuna’s lips at the sight of Mukuro’s annoyance.

 

 

The next words the Vongola Boss said caused Mukuro’s trident to materialise. The Mist guardian’s irritation was apparent from his expression as he began to attack Tsuna, aiming for the brunet’s throat. In the process of dodging Mukuro’s attacks the floors, walls, and windows were destroyed. Somewhere in the back of Tsuna’s mind, he felt like sobbing at the sight. The Vongola Boss didn’t know why but, the word “paperwork” had appeared within his mind. Lost in thought, Tsuna was almost impaled. Jumping back in time, he avoided being skewered by his Mist guardian. Suddenly, Tsuna bumped into someone. Turning around, his violet eyes clashed with steel-grey.

 

 

Mukuro had stopped his attack at the sight of the skylark. A smirk settled upon his face at the sight of the two. Since Tsuna acted like Kyoya, he expected the too to clash. But then, he smirk slowly began to vanish at the sight of their interaction. “Carnivore.” Tsuna addressed the Cloud guardian with a narrowed gaze. “Hn.” Kyoya said as he scrutinized his omnivore of a boss, noticing the change easily. His gaze soon turned over to Mukuro before returning to Tsuna. A silent message passed between the two as a sense of worry began to overcome Mukuro. Slowly, a smirk graced their lips as they turned toward Mukuro with their weapons ready. “We’ll bite you to death.” Speaking simultaneously, they launched themselves toward the panicked Mist guardian.

 

 

Verde blinked slowly at the sound of an explosion while Reborn was smirking. “Who do you think Dame-Tsuna will imitate next?” The hitman asked as he took a sip of his coffee. Before the scientist could even reply to the question, he was interrupted by a loud scream. “EXTRRRRREEEEMMMMME!” Verde sighed before saying, “You just had to ask.”


	3. Sun User

“This can not be happening. This can not be happening.” Sitting in a corner and , rocking back and forth was none other than Hayato. The Storm guardian’s clothes were torn and his hair was sticking up in random places. Slowly and quietly, Takeshi made his way over toward Hayato. Placing his hand on Hayato’s shoulder he said, “Hayato, what happened?” The Storm guardian stopped his rocking before his shoulders began to shake. The Rain guardian began to feel uncomfortable by the weird way his friend was acting. He started to back away, his eyes staring warily at his shaking friend.

 

 

“It's the Tenth..” Hayato's voice was hoarse as he spoke. “What about Tsuna?” Once again Hayato was quiet before he began to laugh, causing Takeshi to take a couple more steps back before freezing at the sight of dull green orbs. Hayato’s eyes were filled with the emotion of horror and fear. Slowly, Hayato raised his hand and pointed toward the door leading to one of Ryohei's training rooms. “It lies in there.” Before Takeshi could ask what he meant, Hayato fell unconscious.

 

* * *

 

 

“EXTREEEEME PUSHUPS!” Tsuna yelled with the emotion of vigor. His yellow orbs were shining brightly, giving off an unnatural glow. “EXTREEEME SIT-UPS!” Quickly switching from one exercise to another, Takeshi could barely keep up with the movement of his boss. From what he was seeing right now, the Rain guardian’s expression was one of confusion and slight fear. Abruptly, Tsuna halted from doing his exercise to slowly turning his gaze over to Takeshi. For some reason, when they made eye contact, he felt his heart skip a beat.

 

 

Of course, the Vongola's Boss’s heart was probably beating faster than a cheetah could run at the moment. “TAKESHI, EXTREMELY NICE FOR YOU TO JOIN US!” It was none other than the Sun guardian Ryohei. He grinned at his fellow guardian as he made his way over to him, Tsuna following close behind. “HAVE YOU DECIDED TO JOIN US?!” Ryohei questioned. Letting out a shaky laugh, Takeshi was about to deny before he had to dodge an incoming fist.

 

 

“EXTREME TRAINING, TAKESHI! YOU CAN'T LEAVE WITHOUT TRAINING FIRST, RIGHT RYOHEI?!” The Sun guardian placed his hands on his hips and released a loud laugh while saying, “YOU'RE EXTREMELY RIGHT!” Next thing that happened was a blur to Takeshi as he tried to avoid being punched. Both Tsuna and Ryohei attacked him while yelling EXTREME. The Rain guardian understood why Hayato was afraid. While Takeshi was dodging for his life, Lambo was making his way toward their location. Of course, he was heading that way to bug a certain Storm guardian. Seeing Hayato unconscious and lying in a corner freaked him out. Although, the child within him caused him to poke Hayato’s unresponsive body.

 

 

At the sound of something being dragged, Lambo stopped his poking. His attention turned toward the opened door across from him. A tanned hand reached out from the darkness, causing him to tense up in fear. Slowly, he saw that the hand was connected to an arm which was connected to the body of his fellow guardian. Suddenly, Takeshi looked up and made eye contact with Lambo. The Rain guardian had a deranged expression while he uttered one word to the scared Lightning guardian. “Run.” Lambo didn't understand why Takeshi told him that until his green eyes made eye contact with a pair of yellow ones.

 

 

Located in the kitchen, Reborn was sipping on a fresh cup of coffee before almost choking at the sound of a girly scream of fear. Clearing his throat he said, “Hm, that sounded like Lambo.” Showing no concern about the scream, he took another sip of his coffee.


	4. Mist User

Normally, the female counterpart of the Mist would be with Kyoko and Haru, enjoying the multiple cakes offered at a bakery near the Vongola mansion. Although, her normal routine with the girls took a rather strange turn today. Instead of tasting cakes with Kyoko and Haru, her boss had joined her instead.

 

 

Soft indigo eyes slowly roamed across the names of each cake within the display before settling upon a certain one then, moving on to another next to it. Ignoring the gawking from those in the bakery, Tsuna continued looking for a cake. Of course, the reason the other customers were staring at him was because of the Mist flame flickering brightly upon his forehead and, the fact he wasn't freaking out about it.

 

 

A conflicted expression appeared as he tried to decide which cake he wanted. Looking away from the display, Chrome turned her attention toward Tsuna. Smiling, she asked, “Boss, do you want the chocolate and the strawberry cake?” Turning his attention toward his Mist guardian, he nodded with a smile before moving to get them a table.

 

 

After receiving Tsuna's answer, Chrome went to the cashier to get their desserts. She didn’t know what caused the change in Tsuna’s personality but, she didn't really care because she was spending time with her beloved boss. Although, she couldn't help but recall the situation that happened earlier before Tsuna's personality strangely resembled her own.

 

* * *

 

 

When Chrome walked into the kitchen to fix herself a glass of water she stumbled upon a sight she did not expect to see. Standing in the center of the kitchen was Mukuro and her boss. Although, that was not what had her extremely confused and slightly scared. Tsuna, for some reason, was wearing an outfit that was strangely similar to Mukuro's. His hairstyle and smirk eerily reminded her of Mukuro, too. Also, his eyes were a dark indigo along with a Mist flame flickering brightly upon his forehead. Before Chrome could question about what was happening, Mukuro spoke up. “Kufufu, you dare mock me, Tsunayoshi?” He asked with a strained smile, his eyebrow twitching from his irritation.

 

 

Tsuna’s smirk only widened at the sight of Mukuro’s irritation before he replied. “Kufufu, and why would you think I’m mocking you?” Gritting his teeth in anger, his trident materialized within his hand. Gripping the hilt tightly he said, “You’ve stolen my outfit and copied my hairstyle.” Raising an eyebrow in question, Tsuna gave a small shake of his head. “I believe that is where you are wrong. I came up with this outfit and hairstyle before you. It is you who is copying me.” Mukuro began to take slow and deep breaths, trying to calm down his simmering anger.

 

 

Then, an idea appeared within his mind. “How about a battle then? Whoever tops the other with their illusions they will have to change their attire completely.” Tsuna hummed quietly in thought before nodding in agreement to Mukuro’s terms as he said, “Alright. And when I win, I will possess your body, too.” Before Mukuro could react at Tsuna’s demand the kitchen’s appearance had changed into an earthy terrain. The sun shined brightly, causing Mukuro to gasp in surprise from the intense heat. It took him and Chrome a few seconds to recover, realizing that it was a simple illusion. Both Mist guardians were surprised at how strong Tsuna’s illusion was.

 

 

In an instant, Mukuro countered Tsuna’s illusion with an icy terrain, the frigid air causing Tsuna to shiver slightly. A smirk graced his lips before he began to make multiple illusions at once, making it harder for Mukuro to counter. As quickly as the battle had started, the quicker it came closer to an end. The two men were gasping for breath, Chrome watching with an expression of awe. Catching his breath, Tsuna stood up straight before grinning at Mukuro. “Kufufu, I win.” Before Mukuro could find the time to counter, he found himself sitting in a chair near a desk. His heterochromatic eyes slowly spotted the multiple stacks of paper sitting on the desk, rising ever so slowly toward the ceiling and beyond.

 

 

Panicking, Mukuro tried to get up before finding his legs handcuffed to the chair along with a pen held within his hand. Before he knew it, he was constantly signing papers. Over and over again, he was reading documents and signing before he couldn’t take it anymore. His eyes rolled to the back of his head before he passed out. After Mukuro fell unconscious, the illusion went away to reveal the kitchen again. Smirking, Tsuna made his way over to Mukuro’s motionless body before stopping. Slowly, Chrome made her way over to Tsuna while asking, “Boss, are alright?” Slowly, the trident in his hands disappeared along with his eyes turning into a softer shade. Quietly, Tsuna turned his gaze over to Chrome and nodded.

 

 

After that, Chrome had suggested they go to a bakery. 


	5. Lightning User

Verde had received an incredible amount of data from the way the rainbow bullet’s effect had upon Tsuna. Reading over his notes, the scientist concluded that Tsuna would most likely impersonate the rest of his guardians. Muttering quietly to himself, he began to list off the effects the rainbow bullet had so far. Gently, he tapped his pen against his chin in thought as he said, “So, who will he become next?” At that exact moment an explosion sounded off in the distance along with a loud and obnoxious laugh. It caught the lightning arcobaleno by surprise, causing him to drop his clipboard. While he went to pick it up his clipboard Reborn came strolling in with a cup of coffee.

 

Sitting back up, Verde ignored Reborn as he went back to thinking. Next thing he knew, the same loud and obnoxious laugh came closer. Tsuna burst inside the room, his sky flame and eyes shining an emerald green. Laughing loudly Tsuna pointed and yelled, “There you are, Reborn!”Freezing, the lightning arcobaleno expression turned into one of horror. The Vongola don reminded Verde of his annoying lightning guardian Lambo. “Oh no.” As soon as he said that, Tsuna came running toward Reborn. As Tsuna tried to get Reborn’s attention, the hitman only ignored him as he drank his coffee. “Don’t ignore me!” Tsuna yelled again before he got an idea.

 

With an expression of fear, Verde watched Tsuna reach in his hair and pull out a pink hand grenade. Grinning childishly, he pulled out the safety ring and threw the grenade at Reborn before running toward the door. An explosion sounded as soon as he made it out of the door. “Got you now, Reborn!” Laughing, Tsuna went back into the room before freezing up in fear. The explosion had also hit Verde because, when Tsuna had pulled out the grenade a few more had fallen out and rolled away. Although, that was not what had the Vongola don scared. Reborn’s coffee cup laid on the ground, his suit ruined by the coffee that had spilled. Verde’s clipboard laid in ruins on the floor, his pen nowhere in sight.

 

Both arcobaleno’s were radiating murderous intent, their eyes shining with malice. Standing up Reborn made his way toward Tsuna while saying, “You’re not getting away with this, dame-Tsuna.” Pushing up his glasses, Verde stood up as well. “I agree, you’ve ruined my research.” Tears welled up in Tsuna’s eyes as he ran out of the room yelling, “I’m scared!” Not a second later, Reborn and Verde went after him.

 

* * *

 

Tsuna was plastered against the wall of the hallway, his eyes holding the emotion known as fear. Quietly, he peeked his head around the corner searching for any signs of Reborn or Verde. ‘Stupid Reborn, stupid Verde,’ he thought with a frown. When he saw that the coast was clear he stepped around the corner with a grin before the sound of a gun went off. A shriek of pain leaves his mouth as he quivers, a stinging pain on his cheek. Slowly, he turned around and saw Reborn.

 

The hitman’s gaze was hidden by his fedora, the barrel of his leon gun smoking. “Nowhere to run, dame-Tsuna.” Tsuna  childishly stuck out his tongue at him. “You don't scare me, Reborn!” Reborn smirked at the sight of his childish bravery as a loud thumping sound was heard. A large Gola Mosca appeared from around the corner, causing the Vongola don to quiver at the sight. He tried to turn and run the other way before screaming and ducking down when a missile was sent at him.

 

The projectile flew past his head before crashing into a wall down the hall and blowing up, causing the side of the mansion they were on to shake. Verde walked from behind it and said, “You’ll pay for ruining my research.” Tsuna took a step back as tears welled up in his eyes. “Gotta...stay...calm.” The two Arcobaleno’s eyes widened when they realized what was about to happen. Before they could do anything, the young boss broke out into tears. He reached in his hair and began throwing grenades all over the place.

 

The explosions went of spontaneously as they fell on the ground or against the walls. During the commotion, Verde and Reborn took cover or dodged the incoming projectiles. Through all the smoke and debris Tsuna managed to calm down a little and make a run for it. He had ran back into the living room, dodging falling debris. He panted as he tried to regain his breath. He took a couple of deep breaths in and out before he relaxed and stood up straight.

 

Reborn and Verde came running back in before pausing at the sight before them. Tsuna eyes and sky flame were no longer an emerald green, but now a light azure. Laughing Tsuna asked, “What’s the problem?” 


	6. Rain User

The rain flame that burned brightly upon his forehead indicated he was now representing his rain guardian. Laughing Tsuna asked, “What’s the problem?” Reborn and Verde didn’t answer as they stood frozen to the spot, both surprised by the fact Tsuna changed personalities so quickly.

 

Their initial actions of taking the life of the Vongola don had wavered for a moment, very briefly, before Reborn motioned for Leon to crawl onto his hand and shift into a familiar green gun. Verde followed Reborn’s example and pulled out a small remote. He pressed a the red button and a rumbling sound was heard, a large gola mosca heading into the room.

 

Tsuna’s carefree laugh halted as his expression became a little confused, a wary smile forming on his face. Next thing the Vongola don knew, he was running down the hallway.

 

Explosions continued to go off all around him, glass shattering, and the Vongola mansion shaking. Amongst this chaos, Tsuna was laughing with a carefree expression. ‘Is this a mafia version of tag? Or is it training?’ He wondered as he dodged another bullet-shaped projectile.

 

The chase had carried on throughout the day, the two arcobaleno being very determined to take Tsuna’s life, if not hurt him to some degree. Although, along the way Tsuna had ran into Takeshi.

 

**“** Want to play baseball?” Tsuna asked with an easy-going expression, all thought of being chased pushed to the back of his mind. Takeshi’s expression matched his as he said, “Sure!”

 

When Reborn and Verde saw the exchange, the two headed the opposite way. Tsuna and Takeshi headed out together, unaware of the danger that they were going to cause by playing a sport they loved.  


	7. Storm User

After a traumatic experience of having to play baseball with Tsuna and Takeshi, Hayato had decided to lock himself in his room for a while. He didn’t get much sleep during the days he remained in his room. Every time he closed his eyes, he’d see the two laughing carefreely.

  
As much as Hayato had wanted to help his boss, he didn’t have the courage to face him while he was portraying as Takeshi. Just remembering the seemingly harmless baseball game made him realize all his fears had come true. He could only question why Verde would come up with idea of creating the Rainbow bullet. He had only recently found out this information from Reborn.

  
Then, one day when Hayato actually managed the courage to come out of his room he was annoyed by the constant sounds of explosions. Assuming it was Lambo messing around again, he stalked off to find out where the explosions were happening.

  
Each loud boom sounded eerily familiar to Hayato, but he shook of uneasy feeling and continued stomping toward his destination. “STUPID COW, STOP MAKING ALL THAT DAMN RAC-,” his words slowed, “et…” With a scowl on his face, eyes shining a bright crimson, and storm flaming burning on his forehead, Hayato was eerily reminded of himself when he looked at Tsuna.

  
Lambo was on the ground dazed and quiet from what he had experienced from Tsuna’s irrational and angered outburst. When Tsuna looked over at Hayato, the storm guardian could only meekly apologize and quietly head out of the room with an expression showing an unrecognizable emotion.


	8. The Original

After everything that has happened...

 

Verde had received an incredible amount of data from the Rainbow bullet’s effect upon Tsuna. The scientist read over his charts and notes he had made along the way while making observations. The sudden personality changes thanks to the Rainbow bullet had various effects upon Tsuna, especially those around him. Verde concluded that the bullet worked rather well, although minor changes could be made for later testing to get more improved results.

 

He typed away on his computer, implementing his newfound data. With each click of a key, his eyebrow twitched in irritation every time a slurp was heard. “May I ask why you’re here?” He turned to look at Reborn. “And why is that in my laboratory?” The hitman smirked and took another sip of his coffee as he lounged in a fancy red Absolom Roche.

 

“Dame-Tsuna has called us for a meeting.” Verde sighed and turned in his chair to face him. “I’m assuming it's to discuss what has happened in the past week.” Reborn smirked and nodded, before getting up and heading out of the lab. Sighing again, Verde got up and followed after him. He would rather stay in his lab to focus on his research, but at the moment he would have to focus upon that later and see what the Vongola don wanted.

 

Reborn and Verde headed down the hallway to Tsuna’s office, taking their time. They noticed the door was open to the office, so there was no need for them to knock as they walked inside. Although, a peculiar sight stood outside of Tsuna’s office.

 

For some reason Takeshi looked dizzy, Hayato was on the ground unconscious, Lambo was shaking in fear, Mukuro was strangely silent, Kyoya looked irritated, Ryohei was laughing and shouting EXTREME, and Chrome was sighing wearily.

 

When they reached the entrance to Tsuna’s office, they were greeted by a loud yet familiar yell.

 

“VOOOOOOOIIIIIIII, WHAT TOOK YOU SO LONG?!”

 

Both arcobaleno froze in place. The effects of the Rainbow bullet hadn’t worn off like Verde had expected. “What have I done?” He muttered weakly. 


End file.
